A porous thiosemicarbazide functionalized covalent organic framework served as sensitive fluorescent sensor for Hg 2+

The detection of heavy metal pollution in food and environment is of great significance for environmental pollution control and human health. 1,3,5-Tris(p-formylphenyl)benzene (TFPB) and thiosemicarbazide (TS) were used as building blocks to construct a thiosemicarbazide functionalized covalent organic framework (COF) through Schiff base condensation reaction. Hg 2+ ions can significantly enhance the fluorescence of the prepared COF-TFPB-TS, and thus COF-TFPB-TS can be utilized for highly selective and sensitive detection of Hg 2+ ions. Moreover, COF-TFPB-TS showed high performance for detecting Hg 2+ in fresh fruit juice, mineral water and tap water, which demonstrated its ability to be applied in real sample testing.